Subtree is a helper utility for working with git subtrees. Easily add, update, and remove subtrees from your git repo.

subtree

#!/bin/bash

# subtree -- a utility to help working with git subtree's
# creator: inhies
# 24 November 2013

version=1.1.1

function usage() {
	case "$1" in
	"")
		echo "Usage: subtree <add | update | rm>"
		;;
	"add")
		echo "Usage:  subtree add <remote name> <git url> <branch> <prefix>"
		;;
	"update")

		echo "Usage: subtree update <prefix | 'all'>"
		;;
	"rm")
		echo "Usage subtree rm <prefix>"
		;;
	esac
	exit 1
}

# Check if we are in the root of a git repository.
isGit=$(git rev-parse --git-dir 2> /dev/null)
if [ !  -d .git ]; then
	if [ "$isGit" == "" ]; then
		# Check for a blank response, indicating a non-existant git repository.
		echo "subtree: You are not within a git repository"
		exit 1
	else
		# We are in a git repository, but not in the root of it, where we need to be.
		echo "subtree: Subtree must be ran from within the git root directory, `dirname $isGit`"
		exit 1

	fi
	exit
else
	if [ "$isGit" != ".git" ]; then
		# A .git folder exists in this directory, but git says we aren't actually in a repository.
		echo "subtree: A .git directory exists, but this doesnt seem to be a valid git repository"
		exit 1
	fi
fi;

declare -A rawMap # Global associative array to hold raw .subtrees lines

# Load the subtrees file in to the map.
function loadSubtrees(){
	while read line
	do
		temparray=( $line )
		rawMap[${temparray[0]}]=$line	
	done < "./.subtrees"
}

function add() {
	# Add the remote and return if there is an error
	git remote add -f $1 $2 
	if [ "$?" -ne "0" ]; then
		return
	fi
	git subtree add --prefix $4 $1 $3 --squash
	# If there was an error adding the subtree, remove the remote we just added
	if [ "$?" -ne "0" ]; then
		git remote rm $1
		return
	fi
	echo "$1 $2 $3 $4" >> .subtrees
	git add .subtrees
	git commit -m "Update .subtrees for $1"
}

# name prefix
function remove() {
	echo "subtree: Removing remote $1"
	git remote rm $1
	if [ "$?" -ne "0" ]; then
		echo "subtree: Erorr removing remote $1"
		return
	fi

	echo "subtree: Removing files from $4"
	rm -rf ./$4
	if [ "$?" -ne "0" ]; then
		echo "subtree: Erorr removing files from $4"
		return
	fi

	git rm -r $4
	if [ "$?" -ne "0" ]; then
		echo "subtree: Erorr removing files '$4' from git"
		return
	fi

	echo "subtree: Removing $1 from .subtrees file"
	PREFIX=$(echo "go/.vim/bundle/gocode" | sed -e 's/[\/&]/\\&/g')
	sed -i".bak" "/$PREFIX/d" .subtrees
	if [ "$?" -ne "0" ]; then
		echo "subtree: Erorr removing subtree $1 from .subtrees file"
		return
	fi
	echo "subtree: old .subtrees file has been copied to .subtrees.bak"

	git add .subtrees
	git commit -m "Removed subtree $1 from '$4'"
	if [ "$?" -ne "0" ]; then
		echo "subtree: Erorr commiting removal of subtree $1"
		return
	fi
}

function update(){
	git fetch $1 $3
	if [ "$?" -ne "0" ]; then
		return
	fi
	git subtree pull --prefix $4 $1 $3 --squash
}


case "$1" in
"-v" | "--version")
	echo "subtree version $version"
	exit 0
	;;

"update")
	loadSubtrees
	case "$2" in 
	"all")
		for v in "${rawMap[@]}"; do 
			update $v
			if [ "$?" -ne "0" ]; then
				echo "subtree: error updating subtree:\n\t$v"
				exit 1
			fi
		done
		;;

	*)
		if [ "$2" == '' ]; then
			usage "update"
		fi
		if [ "${rawMap[$2]}" == "" ] ; then 
			echo "subtree: $2 is not a subtree item. Check .subtrees file"
			exit 1
		fi
		update ${rawMap[$2]}
		if [ "$?" -ne "0" ]; then
			echo "subtree: error updating subtree $2"
			exit 1
		fi
		;;
	esac
	;;

"add")
	loadSubtrees
	if [ "${rawMap[$2]}" != "" ] ; then 
		echo "subtree: $2 already exists"
		exit 1
	fi

	if [ "$5" == '' ]; then
		usage "add"
	fi

	add $2 $3 $4 $5
	if [ "$?" -ne "0" ]; then
		echo "subtree: error adding subtree $2"
		exit 1
	fi
	;;

"rm" | "remove")
	if [ "$2" == '' ]; then
		usage "rm"
	fi

	loadSubtrees
	if [ "${rawMap[$2]}" == "" ] ; then 
		echo "subtree: $2 is not a subtree item. Check .subtrees file"
		exit 1
	fi

	remove ${rawMap[$2]}
	if [ "$?" -ne "0" ]; then
		echo "subtree: error removing subtree $2"
		exit 1
	fi
	;;
*)
	usage
	;;
esac